Resources and Energy Minister Gary Gray said he is "deeply sorry" after last night relaying incorrect advice at an official function that the former South African president had died.

"I apologise unreservedly and am deeply sorry to have relayed what I thought was reliable advice," Mr Gray said in a statement released today.

Mr Gray made the comments while addressing a Minerals Council of Australia dinner in place of former Prime Minister Julia Gillard directly after the ALP leadership spill last night.

The dinner was at Parliament House.

Mr Gray has also apologised to the South African High Commissioner over the embarrassing mistake.

His comments came after rumours circulated on Twitter that Mr Mandela, who is gravely ill in a Pretoria hospital, had passed away overnight.

Mandela is in critical and is on life support at a local hospital. The 94-year-old former president was admitted to the Pretoria hospital on June 8 to be treated for what the government said was a recurring lung infection.

Mandela was jailed for 27 years under white racist rule. He was freed in 1990 and became South Africa's first black president in 1994. Sadly, according to South African media, some close relatives are said to have already begun preparations for the 94-year-old South African first black president, though it is strongly against the Xhosa culture to talk about someone's death while he is still alive.